多花黑麦草根际土壤丛枝菌根真菌对早稻生长的影响

为了探究“黑麦草(Lolium multiflorum L.)-水稻(Oryza sativa L)”草田轮作(Italian Reygrass-Rice,简称IRR)系统中冬种黑麦草对土壤丛枝菌根真菌(Arbuscular Mycorrhizal Fungi,简称AMF)的效应,以及该效应对后作水稻生长的影响,在冬种一季黑麦草大田试验地采集土壤,分析种草土和冬闲土土壤理化性状及土壤中AMF的孢子密度,采用湿筛法倾析AMF孢子.对种草土和冬闲土土壤分别进行灭菌、不灭菌和灭菌并回接AMF共六组处理,然后在室内盆栽水稻.结果表明:冬种一季黑麦草对土壤理化性质的影响未达到显著水平(p>0.05),但极显著地增加了土壤中的AMF孢子密度(p<0.01).冬种黑麦草能够增加后作早稻的株高、叶片数、分蘖数等生长指标,但对早稻的地上部生物量和产量影响不显著(p>0.05).灭菌处理显著的提高了早稻的千粒重和产量.无论是种草土和冬闲土,回接AMF都能在一定程度上增加早稻的产量和千粒重.这些结果初步表明土壤微生物群落可能是影响水稻产量的一个重要因素,AMF对水稻生长具有一定的积极作用.冬种黑麦草能在一定程度上提高土壤AMF密度,改良土壤微生物群落结构,进而促进早稻的生长.

Effects of Arbuscular Mycorrhizal Fungi in the Rhizosphere of Italian Ryegrass on Succeeding Rice Growth

This research studied the effects of winter cropping Italian ryegrass(Lolium multiflonim L.) on the soil properties and spore density of arbuscular mycorrhizal fungi(AMF),and their influences to the growth of rice,in an Italian ryegrass-Rice Rotation(ERR) system.The differences in the physical and chemical properties and the spore density of AMF) between the farmland soil in a paddy field of ERR system and in an idled paddy field(control) were investigated.The soil used for rice cultivation was applied to three treatments:γ-ray sterilization,AMF inoculation afterγ-ray sterilization and the control.The results showed that the winter cropping Italian ryegrass had no significant effects on the soil properties,while it significantly increased the density of AMF spores in soil(p<0.01).It could also significantly improve the plant height, leaf number and tiller number of rice,while the improvement to the above-ground biomass and the rice yield were not significant(p> 0.05).The sterilization treatment clearly improved the thousand kernel weight and yield of rice.The AMF inoculation treatment promoted the thousand kernel weight the yields of rice either in the IRR or CK field.These results suggested that soil micro-organism community is an important influencing factor to rice yield,and AMF has a positive effect on the growth of rice.Winter cropping ryegrass could increase the density of AMF spore and improve the soil micro-organism community structure,thus promoting the growth of rice.